Just to check: Are those roof (straight barrel) or porro (front lenses not
on axis with the back) binoculars? Near as I can tell, that is a roof prism model.
As such it would have sustained some very severe damage to have that problem.
If yout shine a flashlight in and look into the front you might be able to see
either the front lenses or a 'focuser lens' inside moving when you move the focus
wheel. It may show you what's wrong in the way it moves. For porro
binoculars, you can actually tug the eyepieces up and down a little and see if they
move too much, if they 'seesaw'. etc.
I suspect impact damage in either case.
If worse comes to worse, binoculars of similar quality and design can be had
for less cost now. Things have been competitive since then.